Answer Posted / dinesh kumar

Assumed the transformer vector group is DYn11;
1.1U1V1W-which is primary -Delta Connection
2.2U2V2W- Which is secondary-Star connection
3.join 1U& 2U terminals
4.Supply 1U-1V-1W 440v Measured
a.1U-1V
b.1V-1w
c.1W-1U
d.1W-2W
e.1V-2W
f.1V-2V
g.1W-2V
h.1U-2N
i.1V-2N
TO CHECK
1.1V-2W=1V-2V
2.1W-2V>1W-2W
3.1U-1V=1V-2N+1U-2N
From above check(1,2,3) the vector group of transformer is
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